Attic Greek was the dialect of Attica (around Athens) before Alexander, c 500 - 300BC. Koine was the vernacular that spread around the Hellenistic world after A

Attic Greek was the dialect of Attica (around Athens) before Alexander, c 500 - 300BC. Koine was the vernacular that spread around the Hellenistic world after Alexander's conquests, was used to write the New Testament and in the Eastern Roman Empire / Byzantine Empire. Attic survived as a literary / prestige dialect because important philosophical works and plays and such were written in it, but it was the vernacular of the region when those plays, etc. were written. The general progression of Greek, very simplified, can be said to be Homeric -> Attic / Ionic / other dialects -> Koine (mostly from Attic & Ionic) -> Medieval -> Modern